Lithium ethynyltrialkylborates

Lithium ethynyltrialkylborates synthesis of methyl ketones. Lithium acetylide reacts with trialkylboranes at -78° (THF) to give lithium ethynyltrialkylborates (1). On treatment with hydrochloric acid one alkyl group migrates from boron to carbon to give (2). A second migration is prevented by addition of base (also at -78°). Oxidation of (2) then gives a methyl ketone... 

Lithium dimethyl cuprate, 209-215 Lithium diphenylarsenide, 341 Lithium diphenyl cuprate, 234 Lithium diphenylphosphide, 340-341, 645 Lithium diphenylphosphinate, 340 Lithium di-n-propyl cuprate, 245 Lithium ethynyltrialkylborates, 324-325 Lithium fluoride, 17... 

Slayden, S.W. (1981) Relative migratory aptitudes of alkyl groups in the iodination of lithium ethynyltrialkylborates. 

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